Sheet feeding mechanism



1955 H. o. STOEVER SHEET FEEDING MECHANISM Filed March 26, 1962 INVENTOR. HANS 0. STOEVER ATTORNEYS United States Patent 3,165,312 SHEET FEEDING MECHANISM Hans 0. Stoever, Rochester, N.Y., assignor to Eastman This invention relates generally to transport mechanisms, and more specifically to an improved sheet-feeding mechanism.

It is generally old in the art to provide a sheet-feeding mechanism having a driven feed roller that is movable into engagement with a stack of sheets. In sheet-feeding mechanisms of this type, it is necessary to manually raise the mechanism from the base of the storage compartment or from a stack of sheets therein to permit insertion of a new stack of sheets into the compartment. The sheetfeeding mechanism is then lowered into engagement with the stack of-sheets. Also, in these mechanisms, the feed roller is directly coupled to the drive motor so that as soon as the drive motor is energized, the feed roller is immediately driven. I

Applicants improved sheet-feeding mechanism permits the insertion of a stack of sheets into the storage compartment without necessitating raising the sheet-feeding mechanism, and further includes a lost motion connection between the feed roller and drive motor that permits the motor to come up to speed before the feed roller is struck and driven.

It is therefore one of the objects of .the present invention to provide an improved sheet-feeding mechanism that will allow the insertion of a stack of sheets into a storage compartment without necessitating manually raising the sheet-feeding mechanism out of engagement therewith.

Another object of the invention is to provide an improved sheet-feeding mechanism that is of simple design and construction, thoroughly reliable and efficient in operation, and economical to manufacture.

A further object of the invention is to provide an improved sheet-feeding mechanism having a lost motion connection between the feed roller and drive motor for allowing the drive motor to come up to speed before the feed roller is driven thereby.

Objects and advantages other than those set forth above will be apparent from the following description when read in connection with the accompanying drawing, in which:

FIG. 1 is a perspective view showing a preferred embodiment of the sheet-feeding mechanism of this invention;

FIG. 2 is a side-elevation view of the sheet-feeding mechanism showing the position of the feeder pick-up device shortly after it is engaged by the leading end of a stack of sheets fed into the storage compartment;

FIG. 3 is a view similar to FIG. 2 showing the sheetfeeding mechanism and feeder pick-up device after the stack of sheets has been partly fed into the storage compartment;

FIG. 4 is a side elevation partially in section showing the feed roller in engagament with the stack of sheets, and the lost motion connection in position to drive the feed roller to advance a sheet, the remaining structure being omitted for purposes of clarity;

FIG. 5 is a view similar to FIG. 4 showing the position of the lost motion connection after the sheet which had previously been advanced by the feed roller is manually pulled out from the storage compartment; and

FIG. 6 is a section view taken along line 6-6 of FIG. 1.

With reference to the drawing, a preferred embodiment of the sheet-feeding mechanism is disclosed comprising a U-shaped frame 8 whose sides 10 rotatably support a feed roller shaft 12. The shaft 12 as seen best in FIG. 6 ro- 3,165,312 Patented Jan. 12, 1965 tatably supports a gear 14 which is axially positioned on shaft 12 by means of washers 16 pressed onto the shaft against each side of hubs 15, 17 integral with gear, 14. Feed rollers 18 made of polyurethane or some similar material are mounted on shaft 12 and compressed against washers 16 by annular members 20 pressed onto the shaft. The shaft 12 is drivingly connected to gear 14 by means of a lost-motion connection comprising a radially extending drive pin 22 secured to shaft 12, and a hub segment 24 of hub 17. The gear 14 is driven by a Worm 26 (see FIG. 1) on one end of a drive shaft 28, the opposite end of the drive shaft having a spring coupling 30 for connection to a drive motor, not shown. The drive shaft 28 is journaled for-rotation in a pair of lips 32 struck out from frame 8 with worm 26 in proper driving engagement with gear 14.

The importance of the lost-motion connection between feed roller pin 22 and gear hub 24 can be best explained with reference to FIGS. 4 and 5. Normally, when a sheet 34 of paper is desired, the operator actuates the drive motor, not shown, by some suitable switch or the like driving drive shaft 28, worm 26 and gear 14 causing one shoulder 36 of hub segment 24 to engage pin 22 for driving feed roller shaft 12 and feed rollers 18 in a clockwise direction, as seen in FIG. 4, for advancing the top sheet 34 from a stack 38 into engagement with a stop member 41). At this point, the operator will normally turn off the drive motor since once sheet 34 engages stop member 40, feed rollers 18 would merely slip over the surface of the sheet. Should the operator now remove the advanced sheet, the sheet during withdrawal as seen in FIG. 5 causes feed rollers 18 and shaft 12 to rotate by virtue of the friction between feed rollers 18,.and sheet 34 through approximately 180 until pin 22 engages the other shoulder 42 of hub segment 24. Now, if the operator should actuate the drive motor to advance thenext sheet of paper, gear 14 and hub segment 24 will have to rotate approximately 180 before shoulder 36 strikes pin 22 to impart driving movement to shaft 12 and feed rollers 18. This lost motion permits the motor to come up to speed before shoulder 36 engages pin 22, and the sharp initial kick that is given to pin 22, shaft 12 and feed rollers 18 causes the top sheet 34 to break away quickly from stack 38, thereby reducing the possibility of double feeding.

Another feature of the invention is the feeder pick-up device wihch is best seen in FIGS. 2 and 3. This pick-up device essentially comprises a U-shaped bracket 44 having elongated slots 46 in each side thereof adapted to receive complementary pins 48 fixed to each side 10 of frame 8. In the operation of this pick-up device, upon insertion of a stack 38 of sheets into a storage compartment, only the base surface 50 of which is shown (see FIGS. 2 and 3) the leading end of stack 38 engages a lip 52 of bracket 44 and moves it in a combined upward and forward direction with respect to pins 48 causing lip 52 to move underneath feed rollers 18 to effectively withdraw them from contact with the stack 38. Consequently, the highly frictional resistance of the feed rollers 18 to the advance of the sheets into the compartment is removed. Further movement of stack 38 pivots the front end of frame 8 about a support rod 54 permitting stack 38 to move underneath without engaging feed rollers 18. When the drive motor is actuated to advance a sheet 34 of paper, feed rollers 18 in engagement with lips 52 initially drive bracket 44 upwardly and in a reverse direction out of engagement with feed rollers 18 which then drop into engagement with the top sheet 34 of paper in stack 38.

The invention has been described in detail with particular reference to a preferred embodiment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as feeding means and movable by a stack of sheets in-' serted edgewise into said compartment from a normal inoperative position in which said separating means is free of said roller, to an operative position in which said separating means is positioned between the outermost sheet of said stack and said feed roller to prevent said feed roller from frictionally engaging said stack and interfering with the entry of said stack of' 'sheetsinto said compartment, said feed roller when driven by said drive means to feed a sheet from said compartment after said stack of sheets has been inserted returns said separating means from its operative position to its inoperative position.

' 2. The invention according to claim 1 wherein said feeding means includes a frame, and said separating means comprises a U-shaped bracket rockably secured to one end of said frame by a pin and slot connection, said bracket having a base adapted to be engaged by the leading end of a stack of sheets inserted into said compartment, said base further having a lip adapted to be moved between said sheets and said feed roller.

3. The invention according to claim 1 wherein said feeding means includes a frame, and said separating means comprises a rockablebracket mounted on said frame.

4. The invention according to claim 3 wherein said bracket is rockably mounted on said frame by means of a pin and slot connection. i

5. In a sheet feeding mechanism for individually feeding sheets one at a time from a stack of sheets located in a compartment, the combination comprising:

a frame;

a shaft rotatably supported by said frame;

a feed troller'mounted on said shaft for rotation therewith, and having a portion of its periphery in constant frictional engagement with the upper sheet of said stack of sheets for feeding saidsheet upon rotation of said feed roller in one direction;

stop means for a sheet fed by said feed roller and positioned a distance from said feed roller that is less than the length of said sheet for stopping said sheet in a fed position with said feed roller in frictional engagement with a trailing portion .of said sheet;

means for driving said feed roller and including, a drive member rotatably mounted on said shaft and having a drive surface movable from a rest position when said drive member is actuated; and

a driven element fixed to said shaft to be engaged and driven by said drive surface, and movable away from said drive surface while said drive means is in said rest position to provide a lost motion connection therebetween when said fed sheet is manually withdrawn from said fed position causing the trailing end of said sheet to rotate said feed roller, shaft and driven element in said 'one direction relative, to said drive surface,. said lost motion'connection between said drive surface of said drive means and said driven element providing for said drive surface when actuatedto feed another sheet being accelerated prior to its striking said driven element to impart a kick to said feed roller'for separating the upper sheet from the remaining sheets in said stack prior tofeeding said sheet to said fed position.

References Cited in the file of this patent UNITED STATES PATENTS 1,606,964 Sexauer Nov; 16, 1926 1,718,968 Littlefield July 2, 1929 2,588,946 Walden et a1. Mar. 11, 1952 2,844,370 Thomas July 22, 1958 FOREIGN PATENTS 406,934 Germany Dec. 4, 1924 

1. IN A SHEET-FEEDING MECHANISM FOR INDIVIDUALLY FEEDING SHEETS ONE AT A TIME FROM A STACK OF SHEETS LOCATED IN A COMPARTMENT, THE COMBINATION COMPRISING: (A) SHEET OF FEEDING MEANS INCLUDING A UNI-DIRECTIONAL FEED ROLLER MOVABLE INTO A SHEET-FEEDING POSITION IN FRICTIONAL ENGAGEMENT WITH SAID STACK OF SHEETS; (B) MEANS FOR DRIVING SAID FEED ROLLER IN SAID SHEETFEEDING POSITION FOR FEEDING A SHEET FROM SAID STACK; AND (C) SEPARATING MEANS MOVABLY MOUNTED ON SAID SHEETFEEDING MEANS AND MOVABLE BY A STACK OF SHEETS INSERTED EDGEWISE INTO SAID COMPARTMENT FROM A NORMAL INOPERATIVE POSITION IN WHICH SAID SEPARATING MEANS IS FREE OF SAID ROLLER, TO AN OPERATIVE POSITION IN WHICH SAID SEPARATING MEANS IS POSITIONED BETWEEN THE OUTERMOSE SHEET OF SAID STACK AND SAID FEED ROLLER TO PREVENT SAID FEED ROLLER FROM FRICTIONALLY ENGAGING SAID STACK AND INTERFERRING WITH THE ENTRY OF SAID STACK OF SHEETS INTO SAID COMPARTMENT, SAID FEED ROLLER WHEN DRIVEN BY SAID DRIVE MEANS TO FEED A SHEET FROM SAID COMPARTMENTS AFTER SAID STACK OF SHEETS HAS BEEN INSERTED RETURNS SAID SEPARATING MEANS FROM ITS OPERATIVE POSITION TO ITS INOPERATIVE POSITION. 